In medieval Europe, many professions were under the control of guilds. These had a monopoly over that profession in their particular city or state, backed up with all the legal power of the monarch. If you weren’t in the guild you couldn’t practice your craft. Except in a few ossified forms they are a thing of the past, but we have to wonder whether that particular message ever reached Western Canada.
An electoral candidate with an engineering degree who practices what any sane person would call engineering, has been ordered by a judge to cease calling himself an engineer. The heinous crime committed by the candidate, one [David Hilderman], is to not be a member of the guild Association of Professional Engineers and Geoscientists of B.C. We get it that maybe calling a garbage truck driver a waste collection engineer may be stretching it a little, but here in the 21st century we think the Canadian professional body should be ashamed of themselves over this case. Way to encourage people into the engineering profession!
Here at Hackaday, quite a few of us writers are engineers. Stepping outside our normal third person, I, [Jenny List], am among them. My electronic engineering degree may be a little moth-eaten, but I have practiced my craft over several decades without ever being a member of the British IEE. No offence meant to the IEE, but there is very little indeed they have to offer me. If the same is true in Canada to the extent that they have to rely on legal sanctions to protect their membership lists, then we think perhaps the problem is with them rather than Canadian engineers. You have to ask, just how is an engineering graduate who’s not a guild member supposed to describe themselves? Some of us need to know, in case we ever find ourselves on holiday in Canada!
Perhaps the most-cited downside of renewable energy is that wind or sunlight might not always be available when the electrical grid demands it. As they say in the industry, it’s not “dispatchable”. A large enough grid can mitigate this somewhat by moving energy long distances or by using various existing storage methods like pumped storage, but for the time being some amount of dispatchable power generation like nuclear, fossil, or hydro power is often needed to backstop the fundamental nature of nature. As prices for wind and solar drop precipitously, though, the economics of finding other grid storage solutions get better. While the current focus is almost exclusively dedicated to batteries, another way of solving these problems may be using renewables to generate hydrogen both as a fuel and as a means of grid storage. Continue reading “Renewable Energy: Beyond Electricity”→
Although the concept of nuclear fission is a simple and straightforward one, the many choices for fuel types, fuel design, reactor configurations, coolant types, neutron moderator or reflector types, etc. make that nuclear fission reactors have blossomed into a wide range of reactor designs, each with their own advantages and disadvantages. The story of the pebble bed reactor (PBR) is among the most interesting here, with its development winding its way from the US Manhattan Project over the Atlantic to Germany’s nuclear power industry during the 1960s, before finding a welcoming home in China’s rapidly growing nuclear power industry.
As a reactor design, PBRs do not use fuel rods like most other nuclear reactors, but rather spherical fuel elements (‘pebbles’) that are inserted at the top of the reactor vessel and extracted at the bottom, allowing for continuous refueling, while helium acts as coolant. With a strong negative temperature coefficient, the design should be extremely safe, while providing high-temperature steam that can be used for applications that otherwise require a coal boiler or gas turbine.
With China recently having put its twin-PBR HTR-PM plant into commercial operation, why is it that it was not the US, Germany or South Africa to first commercialize PBRs, but relative newcomer China?
Although spying is a time-honored tradition, the sheer scope of it reached a fever pitch during the Cold War, when everyone was spying on everyone, and conceivably for both sides at the same time. In an era where both McCarthyism and the character of James Bond enjoyed strong popularity, it should come as no surprise that a project of geopolitical importance like the development of the world’s first supersonic airliner would come amidst espionage, as well as accusations thereof. This is the topic of a documentary that recently aired on Channel 4 in the UK called Concorde: The Race for Supersonic, yet what is the evidence that the Soviet Tu-144 truly was just a Concorde clone, a derogatory nicknamed ‘Concordski’?
At the time that the Concorde was being developed, there wasn’t just the competition from the Tu-144 team, but also the Boeing 2702 (pictured) and Lockheed L-2000, with the latter two ultimately being cancelled. Throughout development, all teams converged on a similar design, with a delta wing and similar overall shape. Differences included the drooping nose (absent on Boeing 2707-300) and use of canards (present on Tu-144 and 2707-200), and wildly different engines, with the production Tu-144S requiring an afterburner on its Kuznetsov NK-144A engines just like the Concorde, before the revised Tu-144D removing the need for afterburners with the Koliesov RD36-51 engines.
Although generally classified as a ‘failure’, the Tu-144’s biggest issues appear to have been due to the pressure on the development team from Soviet leadership. Once the biggest issues were being fixed (Tu-144D) it saw continued use for cargo use and even flying missions for NASA (Tu-144LL) until 1999. Although Soviet spies were definitely caught with Concorde blueprints, the practical use of these for the already overburdened Tu-144 development team in terms of reverse-engineering and applying it to the Tu-144’s design would be limited at best, which would seem to be reflected in the final results.
Meanwhile, although supersonic airliners haven’t been flying since the Concorde retired in 2003, the Lockheed Martin X-59 Quesst supersonic airplane that is being built for NASA looks set to fix the sonic boom and fuel usage issues that hampered supersonic flight. After the L-2000 lost to Boeing so many decades ago, it might be Lockheed that has the last laugh in the race towards supersonic flight for airliners.
(Top image: Tu-144 with distinctive droop nose at the MAKS-2007 exhibition)
Earlier in this series, we made the case for copper being “the metal that built technology.” Some readers took issue with that statement, noting correctly that meteoric iron and gold were worked long before our ancestors were able to locate and exploit natural copper outcroppings, therefore beating copper to the historical punch. That seems to miss the point, though; figuring out how to fashion gold decorations and iron trinkets doesn’t seem like building the foundations for industry. Learning to make tools from copper, either pure or alloyed with tin to make bronze? Now that’s how you build an industrial base.
So now comes the time for us to make the case for our most recent addition to humanity’s stable of industrial metals: titanium. Despite having been discovered in 1791, titanium remained locked away inside abundantly distributed ores until the 1940s, when the technological demands of a World War coupled with a growing chemical prowess and command of sufficient energy allowed us to finally wrest the “element of the gods” from its minerals. The suddenness of it all is breathtaking, too; in 1945, titanium was still a fantastically expensive laboratory oddity, but just a decade later, we were producing it by the (still very expensive) ton and building an entirely new aerospace industry around the metal.
In this installment of “Mining and Refining,” we’ll take a look at titanium and see why it took us over 11,000 years to figure out how to put it to work for us.
Once upon a time, escaping an aircraft was a tricky business. You had to unstrap yourself, fling open a heavy glass canopy, and try to wrench yourself out of a small opening without getting smacked by the tail or chopped up by the propeller. Many pilots failed this difficult task, to the tragic loss of their lives.
Eventually, the human cost was heavy enough and militaries grew strained at having to train new pilots to replace the experienced ones lost to accidents and enemy fire. The ejection seat was developed to make escaping a plane as simple as tucking yourself in and pulling a big red handle. Let’s dive in and learn how it came to be.
It is an interesting fact that the most efficient way to generate electricity — at least so far — is to spin the shaft of a generator. The only real question is how you spin it. Falling water works. Heat from a nuclear reaction is another choice. For many decades, the king of the hill was steam. Now, however, gas turbines rule the electric generator landscape, and [Construction Physics] explains why in a recent post.
With a steam turbine, something burns or otherwise generates heat that boils water. The steam spins the blades, which turns the generator. With a gas turbine, the system compresses air and mixes it with gas. The hot gasses then drive the turbine, which is more efficient than using the combustion to produce steam.
Turns out, the idea for the gas turbine is very old, but material science had to catch up to be practical. Inefficient compressors led to low operating pressures, which was good, in a way, because the materials couldn’t stand the heat and pressure. However, low pressures led to inefficient turbines that were not practical.
The post is long and covers a lot of details about Carnot, Brayton, and Rankine cycles. It is a fascinating read, and we learned a few new things. Bet you will, too.
Turbines are a little like jet engines, but they transfer more power to the turbine blade instead of generating thrust. Turbines show up in odd places today. Some odder than others.